Rewinding machine



1959 L. ROCKSTROM ET AL 2,872,126

REIWINDING MACHINE 6 Sheets-Sheet 1 Filed April 4, 1955 INVENTORS.LEONARD [Packs-ream.

CHARLES AARON.

A TTORNEYS.

Feb. 3, 1959 L. 'ROCK-STROM ET AL 2,872,126

REWINDING MACHINE 6 Sheets-Sheet 2 Filed April 4, 1955 INVENTORS. LEO/VAPD FocKsTEo/ l. BY CHAELE-SAARON.

E' -IAL ,M

ATTORNEYS 5 IL. ROCKSTROM ETAL 2,872,126

REWINDING MACHINE 6 Sheets-Sheet 3 Filed April 4, 1955 mom N S E E N onE K E a V C A m 0A N l E s uw 1 0 w H! r E E em M A 4'! am a E b L Y M B1 E fi @Q li n 0m i w e 3, 19 L. ROCKSTROM ET AL 2,872,126

REWINDING MACHINE Filed April 4, 1955 6 Sheets-Sheet 4 INVENTORS. LEONARD lPocKsT/eoM.

CHARLESAAEON. BY

"e ATTORNEYS.

Feb. 3, 1959 L. ROCKSTROM E'TAL 2,872,126

REWINDING MACHINE Filed April 4, 1955 6 Sheets-Sheet 5 INVENTORS.

LEONARD fiocksreofl. CHARLES AARON- A TTUANEVY.

1959 4L. ROCKSTROM ET AL 2,872,126

REWINDING MACHINE 6 Shets-Sheet 6 Filed April 4, 1955 MUPUES 440 DZISUM.

tate in REWINDHIG MACHINE Application April 4, 1955, Serial No. 498,80914 Claims. (Cl. 242-65) This invention relates to improvements inrewinding machines, and more particularly to improvementsin controlmeans for slittingand rewinding machines.

The invention is shown, by way of illustration, asembodied in a slittingand rewinding machine employing two shafts for supporting two groups ofrewound or rewind rolls, such a machine being referred to in the art asof the duplex type. However, certain features of-the invention areuseful in machines of other types.

In the slitting and rewinding of certain types of; web material, withparticular reference to stretchy materials, usually of plastic,substantial problems have occurred in past apparatus of this characterwhich are attributable to the inability thereof adequately to controlthe pressures acting on the rewind rolls. That is, the web materialwhich is being slit and rewound in most cases shouldbe subjected toassmall contact pressure and tension as is possible commensurate withthe requirement to slit and rewind same upon a rewind shaft.Consequently the forces which act upon the web which normally would tendto distort same, must be minimized in order to attain a desired qualityof the rewound roll.

It is, of course, important in such machines to attain a high qualitycontrol of the rewind rolls, that is, a control of those factors whichwill provide desired roll density, internal tension and quality of rolledge.

Apparatus of this general type of the prior art have'not been capable ofadequate controls of such factors, particularly with respect to stretchymaterials.

Furthermore, apparatus heretofore proposed-have been unable to slit andrewind certain types of web material at high operating speeds, forexample, up to ZOOO'feet per minute.

In slitting and rewinding machines, the mill web passes around aconstant speed roll, known as a contact drum, or a platen drum againstwhich the slitters or cuttersoperate to cut the web-into a pluralityv ofsmaller rewind widths, although slitting may be done at other locations.These smaller widths pass to the rewind rolls which rest against thedriven contact drum, the several rewind rolls being wound upon rewindshafts. Heretofore apparatus of this class has not been able to controladequately the pressure between the rewind rolls and such contact drumnor have such prior art machines been adequately equipped for thepurpose of permitting anoperator. so to control the pressure between therewind rolls and contact drum, such pressure being herein sometimesreferred to as roll-contact drum pressure or contact pressure.

One of the objects of the present invention is to provide novel meansfor controlling such contact pressure where- 'by a superior qualitycontrol of the end product is. at-

tent rolls.

purpose of maintaining the aforementionedminimnnr'uni; form contactpressure or rewind roll-contacfd urn'prles sure, thereby to producesmooth 's'traight-sidedfroils"of uniform density, the system beingadjustable to proyide a heavier contact pressure which, also can beuniformly maintained where needed. 4 Y;

Another object, is to, provide a slitting and rewinding;

machine which, while operating at heretofo'r'efunattaihed productionrates, is capable or ning'ageu anywm trolled and desired roll density,internal" annea pd quality of the side or edge of the rolls, i M

Still another object is toprovide asingle apparatus ofthis characterhthe versatility of which i sisuclith capable ofslitting and winding;lightheaiyf, stre h relatively stiff plastics, and Ianiinatesofall typewax d' r oate ati ekr ft Q hndr l'sj t dth CS d othermaterials. iAnother object is to provide an apparatus of' this char: acter whichcanprovide easily and completely 'con'trol lable rewind roll qualitywherein there is provided, an automatic rewind d nsity. Control meanswhichf'isfad} justable while the apparatus is running: and wherein therewind tension is positively isolated frorn the unwind en; sion,' th atis, the web tension in the region of the. tiflf Wind, pat n r l nd heree. nw h fw h ls bn prevented from building up in the rewind 'regionoftheppar t s St uhhothe object to, r d a parat h h character wherein rolldensity can be commitments,- matigally with high precision betweensubstantial" limits whe eby. he W1 an h r. of sof hr r chhsist y Still afurther. object is to provide noveljm'eanstor antorna tically balancingthe torque. which acts jupohtne I PPQIi IE ai s for he w nsi shaft, sh hw qhe e due to the pull Qtthh Web. bein l l d- P0 l Another object is toprovide novel connterbalan ng means for automatically counterbalancingfthe static Weigh o he wi h ma ia as it hui dhh i he rew n And still afurther object is to prov fe h' thal i s e e h tst was t supporting arms.for the rewind. roll or rolls, .inclu t c (618m of h w sh fl st cturFur er o e d' v ta esjhf h .ihy h iqh wil ore fully app a r mt e'fq hw sdhs f h' ta h i o nec on h h a wmnhh h flta i s h qw; byv w ht xam le hep esent t rr djfh hl the invention H L de novel means Ethic Refer n 9 hv a co any n qrhwi st h whi ths same reference characters indicatethe;same parts varlous views: l

Fig. 1 is a sehematic diagram illustrating one form of apparatusembodying the presentinvent n w' particular reference to theinterconnections fir a'ph nj a 'c ysterhhmp y d th r y; i

F ig; 2 is a side elevationof one form ofapparatu slernbodying thepresent invention and in particular illiistrating the rewind rolls andtheir supporting shaftsfin association with cam control means which inturn govern p ma ntc a ah m an o cou terhalah cih the static weight ofthe rewind rolls as, theyhuildgup in i me e Fig. 3 is a front elevationof the rear pivot'shaftrto which is secured two supportingarmsfonthe-rear rewind f u h figure l a n r in o r sp ing; mean mploy d ou lanh e s icweight ttsuch arms and rewind shaft; 4

. Fig. 4 is a sectional view-takqn substantiallyon line 4 4 of Fig. 3;

Fig. 5 isa frontelevation'of'a couuterbalancing-mechanism for the frontrewind arms and frontjrewindtshaft employed in the apparatus and shows apair of coil springs wound about a central shaftfor this purpose;

Fig. 6 is a sectional view taken substantially on line 6 6 of Fig.

Fig. 7 is a sectionalview taken substantially along line 77 of Fig. 5;

Fig. 8 is a side view of a rewind roll counterbalance valve meansemployed in the invention, including a sliding cam device which isadjustable in terms of the number of inches of the width of the webmaterial wound on the pertinent rewind shaft;

Fig. 9 is a front elevation of the parts shown in Fig. 8;

Fig. 10 is a side elevation of the novel apparatus showing the latter onthe opposite side thereof with respect to that shown in Fig. 2 and inparticular illustrating an offset drive pulley construction wherein theaxis ofeach of the respective drive pulleys for the respective rewindshafts is offset with respect to the pivot axis of its respective rewindarms, for the purpose of counterbalancing the pull of the web actingupon the respective support ing arms; 1

Fig. 11 is a schematic view on a somewhat enlarged scale as compared toFig. 10 and illustrating in greater detail the offset of the axis of thedrive pulley for each rewind shaft with respect to the pivot axis of thesup porting arms for such shaft and also illustrating schematically theseveral moment arms and moments which are created in thecounterbalancing of the web pull;

Fig. 110: is a schematic showing of certain parts of Fig. 11 in anintermediate position and also illustrating schematically certain of themoments and moment arms instantaneously occurring; and

Fig. 11b is a schematic showing in side elevation of counterbalancingmeans which performs a function analogous .to that of the means shown inFig. 11.

Fig. 12 is a graphical showing of the relationship of two of theopposing moments which act about the axis of the front rewind rollsupporting arms.

Referring to the drawings in greater detail, there will now be describedin general and briefly the operation and construction of the apparatuswhereupon the details of the several counterbalancing systems will bedescribed at greater length.

Referring to Fig. 1, the apparatus comprises a slitting and rewinddevice generally designated 20 which includes a pair of rewind shafts 21and 22 which are respectively the front. and rear rewind shafts. Thefront rewind shaft is supported by a pair of rewind arms 23 and 24 whichat the inner ends thereof, that is, the lower ends as viewed in thisfigure, are mounted for angular move-' ment about a fixed or primaryaxis, such inner ends of the arms thus being mounted upon a pivot shaft25 which is journaled for angular movement in the frame of theapparatus.

The rewind shaft 22 in turn is supported by a pair of rewind arms 26 and27 which, at the inner ends thereof, are mounted upon a pivot shaft 28which also is mounted for angular movement in suitable journals in theframe of the apparatus whereby said rewind arms 26 and 27 also areadapted for angular movement about a primary axis, namely, that of theshaft 28.

The shafts 21 and 22 are shown in raised or spaced relationship withrespect to a contact drum 29, partially about which there passes the webmaterial which is slit and thereafter wound into rolls upon the rewindshafts 21 and 22.

The slitting devices, comprising a plurality of wheel- .like knives forpressing against the contact drum 29, are

briefly described hereinafter but are not a part of this invention. a

I -Th'e co ntact drum 29, as aforementioned, is driven at a constantspeed by any suitable means (not shown) and the rewind shafts 21 and 22are driven at variable speeds,

.which. speeds decrease as the rewind roll diameter increases. The driveand speed control means for said 4 drum 29 and shafts 21 and 22 may besimilar to that shown and described in U. S. Patent No. 2,650,039,granted August 25, 1953, to Thomas N. Carter.

There will now be described the several counterbalancing systems whichare designed respectively for counterbalancing: the static weight of therewind arms and shafts, the static weight of the rewind rolls as therewind diameters build up upon the rewind shafts, and the pull of theweb upon the rewind arms or rewind shafts. The torques effected by suchweights and the web pull act about the primary axis of each of theaforedescribed pairs of rewind arms.

System for counterbalancing the static weight of the rewind shaftsupport arms and rewind shafts Referring now particularly to Figs. 1 and3-7, inclusive, it will be observed that in Fig. 1 there isschematically shown a pair of coil springs 30, 31 which respectively arecoiled about the front pivot shaft 25. Such coil springs at the innerextremities thereof are relatively fixed whereas the outer extremitiesthereof are secured to the respective rewind shaft support arms 23, 24in such a manner that as such support arms shift angularly in acounterclockwise direction towards the contact drum 29, the coilsthereof are wound up thereby increasing the force exerted upon thesupport arms 23, 24 to counterbalance the static weight thereof,together with the weight of the rewind shafts 21.

In greater detail such springs 30 and 31 are shown in Figs. 5 and 7.However, in view of the fact that Fig. l is a schematic showing, thesprings 30 and 31 have been shown coiled directly about the pivot shaft25, whereas in Fig. 5 the springs 30 and 31 are not coiled directlyabout the pivot shaft 25 but in lieu thereof are coiled about anothershaft of this counterbalance mechanism designated 32, which in fact issituated below the pivot shaft 25 but is operatively connected theretoby means of a suitable linkage whereby the torque of the springs 30 and31 is communicated to the pivot shaft 25 and thence to the arms 23 and24.

justable arm 35, is prevented from shifting angularly thereby anchoringtheaforementioned spring extremity 30a. The opposite extremity of thespring 30 at 3% (Fig. 5) is rigidly secured to the shaft 32 by means ofa clamp 36 which is analogous to the clamp 33.

The opposite extremities of the spring 31 are analogously secured toaspring collar, such as 37, analogous to collar 34, and to aclamp 38which is analogous to the clamp 36.

The aforementioned linkage which operatively interconnects the shaft 32to the pivot shaft 25 is partially shown in Fig. 6 and comprises a leverarm 39 and a rod 40 which is pivoted at 41 to one extremity of the leverarm 39, the opposite extremity of the rod 4% being pivotally secured toanother lever arm (not shown) which in turn is attached suitably to thepivot shaft 25.

Referring now to Fig. 3, the counterbalance system for the rear shaftwill be described which differs somewhat from that of Fig. 5 by virtueof the fact that the two opposite counterbalance coil springs 42 and 4-3are associated at the inner ends thereof by means of two spring controlsleeves 44 which are similar but of opposite hand. The spring 42 isoperatively connected'to the system as follows: The outer extremitythereof at 4211 is secured by means of a clamp 45 to a collar-46 whichis secured to the frame of the apparatus, whereas outer extremity 42b ofthe spring 42 is secured by means of a spring clamp 47 to a flange 44aof the lefthand sleeve 44. Analogously the opposite extremities ofspring 43 .are secured respectively by means of spring clamps 48 The twosleeves .44 can be angularly adjusted about the pivot shaft 28 by meansof an adjustable ring device generally shown at 50 consi'ting of a ringportion 51 which is rigidly secured against angular shifting upon theshaft 28 by means of a pin 52 (Fig. 4). A threaded bolt Stla ispivotally secured at 5b]; to the ring portion 51. By means of a threadednut Site, which engages the bolt 50a, inner flanges 44c and 44d,respectively secured to said two sleeve members 44, are caused to shiftangularly within selected limits. This is accomplished by means of anadjustment lug 50d having a here through which passes the aforementionedbolt Stla and which further is provided with trunnions 50a and 56 whichrespectively engage suitable bores in the sleeve flanges 44c and 440..Thus by adjustment of the nut 50, a suitable adjustment of the coils 42and 43 can be effected.

Thus as the rear rewind shaft supporting arms move in a clockwisedirection, as viewed in Fig. 1, the springs 42 and 43 will be adequatelycoiled to counterbalance the moment thereon effected by gravity actingsaid arms 26 and 27 and the rewind shaft 22, such moment, of course,being a varying one and a gradually increasing .one as such arms movefrom their raised position toward the contact drum 29.

System for counterbalan'cing increasing web material weight on therewind rolls Referring now to Figs. 1, 2, 8 and 9, the counterbalancingsystem will now be described for compensating for or counterbalancingthe increasing static weight of the web material as it builds up on therewind shafts 21 and 22.

We have found it desirable to counterbalance the aforementionedgradually increasing web material weight by means of a pneumaticpressure device which exerts gradually increasing pressure upon thesupporting arms for the rewind rolls in response to angular movement ofsuch supporting arms from a selected norm position, the latter position,of course, referring to the position of the arms at the minimum rewindroll diameter which occurs at the outset of the rewind operation.

Further we have found it desirable, in order to insure that an equalcounterbalancing moment is exerted upon both of the supporting arms ofeach pair thereof, to employ two pairs of pneumatic power devices, onefor each arm and in Fig. 1 it will be noted thus that four suchpneumatic power devices are employed. This counterbalancing system willbe described with respect to the rear rewind shaft supporting arms 26,27, it being understood, of course, that an analogous apparatus isemployed for the front rewind shaft supporting arms 23, 24.

The pair of power devices for such rear shaft, in the form shown,comprise pneumatic power cylinders respectively designated 53 and 54which are respectively drivably connected with the support arms 26 and27. The pneumatic devices 53 and 54 are respectively provided withpistons 55 and 56 which are interconnected with their supporting arms 26and 27 by means of piston rods 57 and 58.

Fluid under pressure, preferably air, is directed to the power cylinders53 and 54 under the influence of a control valve 59 which in turn isunder the influence of two different factors: (a) the angular positionof the arms 26 and 27,; and ('0) the sum in inches of the rewind rollwidths on the given rewind shaft, that is, the weight of the rewindrolls in terms of the widths thereof.

Regarding the latter factor, it comprises a prorated share of the weightof the parent roll which is wound upon the rewind shaft. That is, thetotal weight of a parent roll, for example, of sixty inches in width, isknown and if the slitters are so adjusted, for example, to rewind atotal of thirty inches of such width of the parent roll upon a rewindshaft, then the latter factor (b) is 5 adjusted in such a way that itreflects the rewinding of thirty inches of the parent roll.

Alternatively, the total weight of the parent roll need not be known.However, the adjustment for the factor (b) above mentioned is made uponthe apparatus, as will be set forth below, for both the front and therear rewind shafts in such a way that both adjustments reflect the totalwidth of the parent roll in inches (or whatever suitable term isdesired) and consequently an adequate adjustment is made for theprorated share of the parent roll which is ultimately to be wound uponthe rewind shaft.

Consequently, referring to Fig. l, the valve 59, by means of a controlrod 6! is placed under the influence of a control cam 61 which isangularly shiftable in response to angular movement of the support arms26, 27, such cam being suitably operatively interconnected thereto, forexample, to the pertinent pivot shaft 28.

The cam 6i, by angularly shifting upon its axis 62, is capable ofshifting, in the direction of the arrow 63, a ramp element 64 which isadjusted in slope in response to the aforementioned factor (b) inaccordance with the sum of the rewind roll widths in inches,. referencebeing had for this purpose to a suitably graduated scale at 65, theadjustment being made with theaid of a pointer 66.

The aforementioned ramp element 64 is retricted to move in the directionof the arrow 63 by a carriage 67 which, as is well shown in Fig. 9, isrestricted in move .ment in a vertical direction by means of guides 68and 69 which move in vertical grooves 70 and 71, respectively,

which are formed in stationary guideposts 72 and 73, respectively.

in the form shown, the carriage 67 is urged upwardly by means of a coilspring '74 (Fig. 9) which provides the driving power for the carriage 67and hence for the ramp 64, the angular movement of the cam 61 distortingthe spring 74 in response to the angular position of the support arms26, 2'7.

The ramp 64 thus can be adjusted in its angular position about anadjustment shaft '75 thereby to control the slope of such ramp andhenceto superimpose the correction or compensating factor for the sum ofthe rewind roll widths upon the correction factor for the angle of movement of the support shafts 2'6, 27. Shaft 75 is mounted for angularmovement upon arms 75a of the carriage 67.

A cam follower 64a (Fig. 8) in the form of a roller rides upon the ramp64, such follower being mounted for rotation upon an arm 64b which isangularly shiftable about a fixed pivot 64c. The roller 64a is coaxialwith shaft 75 when cam 61 is in its zero or no correction position.

The shaft 75 which supports the ramp 64 can be frictionally held in adesired angular position after it has been suitably adjusted by wellknown clamp means. As is well shown in Fig. 8, the graduations 65 areformed upon a suitable plate 76 which may be secured to the guidepost73.

It will be seen that there is provided for the ramp element 64 anadjustment screw 77 having a lock out 78 therefor, the screw 77 passingthrough a suitable threadedbore 79 formed in the movable carriage 67- ofthe ramp element es.

The fluid pressure, which is under the influence of the control valve59, is directed to both of the pneumatic cylinders 53 and 54 in a mannerto be more fully described herebelow.

Prior to describing the interconnection of the valve 59 with the fluidconduit system for the pneumatic power devices 53 and 54, there will bedescribed the conduit system for conducting fluid under pressure to suchpneu- 'rnatic cylinders for the purpose of raising and lowering the mainfluid pressure line 80 which, forexample, may con- Y 7 tain air underpressure of 60 p. s. i. Such air under pressure is conducted to thepneumatic cylinders'53 and 54 for the purpose of either raising orlowering the rewind shaft 22 by means of a four-way main valve 81 whichis controlled by means of a hand lever 82, the latter being adjustablein position to the position shown in broken lines respectively at theright and left for raise and lower, or alternatively to a centralposition, as shown in solid lines for run as will appear more fullyhereinafter.

The main valve 81 is interconnected to the conduit 80 by means of aconduit 82a, and is respectively connected to the raise sides of thepneumatic cylinders 53 and 54 by means of a conduit 83 which is directedto a check valve 84, the latter having a bypass restriction. As isschematically shown in Fig. l, the check valve 8- is provided with aball check 84a which will permit the pas sage of air towards thecylinders 53 and'54 but not away therefrom, and is also provided with abypass restriction 84b for a purpose that will appear hereinafter. Thecheck valve 84, by means of a conduit 85, in turn is connected to aconduit junction 86 from which emanate conduits 87 and 88 respectivelyconnected to the raise sides ofthe pneumatic cylinders 53 and 54. Thatis, the conduits 87 and 88 are connected to the cylinder chambers whichare in Fig. l to the right of the pistons 55 and 56 and thus on the sidethereof to which fluid is directed for the purpose of raising thesupport arms 26, 27.

The main valve 81 is connected to the lower sides of the aforementionedcylinders 53 and 54 by an analogous conduit system as follows:

A conduit 89 interconnects the main valve 81 to a check valve 90 havinga ball check device and a bypass restriction therein analogous to 84aand 84b, that is, fluid is permitted to pass toward the pneumaticcylinders, not away therefrom, by such ball check and the bypassrestriction is provided therein also for a purpose to appearhereinafter.

The check valve 90 is in turn, by means of a conduit 91, connected to aconduit junction 92 which is respectively connected to the pneumaticcylinders 53 and 54 by means of conduits 93 and 94, the latter conduitsbeing connected to the aforementioned lower sides of their respectivecylinders.

Thus when it is desired to raise the rewind shaft 22, the

main valve handle 82 is moved to the righthand position (Fig. l) whichconducts fluid to the cylinders 53 and 54 by means of the followingpath: conduit 82a, valve 81, conduit 83, check valve 84, conduit 85 andthe conduits 87 and 88. The air under pressure thus urges the pistons 55and 56 to the left, as shown in Fig. 1, thereby raising the support arms26, 27. This pressure is prevented from slamming the support arms 26, 27against their limit-stops (not shown) by means of the back pressureexisting in the lefthand chambers of said cylinders which escapes viathe following path: conduits 93, 94, conduit 91, the check valve 90 (viathe bypass restriction therein), the conduit 89 and an exhaust port inthe main valve 81.

When the support arms 26 and 27 are in their raised position and it isdesired to lower same to an operating position adjacent the contact drum29, the handle 82 is shifted from its righthand or raise position to itslefthand or lower position, as shown in Fig. 1, thereby directing airunder pressure to the lefthand chambers of the cylinders 53, 54 via thefollowing path: 82a, 81, 89, 9t), 91 and 93, 94. The support arms 26, 27are again prevented from slamming against their lower limit-stops (notshown) by means of an analogous air cusioning which is bled from therighthand chambers of their respective cylinders via the bypassrestriction 84b of the check valve 84 and a suitable exhaust port in themain valve 31.

The interconnection of the cam controlled valve 59 into conduit 89 bymeans of a conduit 95 and is onthe oppo- 8 site side thereof connectedto the conduit by means of a conduit 96, there being interposed in thelatter conduit 8. pressure-operated poppet valve 97 which serves thepurpose of isolating the cam control valve 59 whenever the handle 82 ismoved away from the aforementioned central or run position.

The conduit 96 is divided into two portions, namely, 96a, whichinterconnects the valve 59 to the poppet valve 97, and a portion 9611which interconnects said valve 97 to the conduit 85. When the poppetvalve 97 is actuated, it blocks off the conduit 96a, thereby preventingthe leakage of fluid via such conduit 96a.

The poppet valve 97 is opened by a suitable pilot valve 98 which isresponsive to the plating of the handle 82 in the central position, asshown in Fig. l in solid lines.

The poppet valve 97 is closed when the handle 82 is in either the raiseor lower position by virtue of fluid under pressure conducted theretovia a conduit 99 in which the pilot valve 98 is interposed. Thus theaforementioned cam-controlled valve 59 is isolated from the fluid infeedsystem when the handle 82 is in said raise or lower position.

However, when the handle 82 is placed in the center or run position, thepilot valve 98 is actuated in such a way that the pressure normallyacting upon the poppet valve 97 is bled therefrom and the fluid underpressure from conduits 95, 96 is allowed to pass to the cylinders 53, 54via the cam control valve 59, the poppet valve 97 then being open.

It is, of course, understood that the main valve 81 is in a closedcondition when the handle 82 is in the central position thereby insuringthat the full fluid pressure in conduits 95, 96 suffers no leakage andis directed to the pistons 53, 54.

When the fluid pressure is so directed to the cylinders 53, 54 via thecam controlled valve 59, we have found it desirable to introduce as-o-called in-pressure, that is, a pressure acting counter to the fluidpressure coming via the cam controlled valve 59, the purpose for thisbeing to provide a more positive control of the fluid pressurecounterbalancing system to provide a precision control of theaforementioned contact pressure, that is, the pressure of the rewindroll against the contact drum 29.

Accordingly, a hand controlled in-pressure regulating valve 100 isprovided for controlling the flow of air under pressure to the lefthandchambers of the cylinders 53, 54. Such in-pressure is conducted to thecylinders 53, 54 by means of a conduit 101, which interconnects theregulating valve with the main air line 80, a conduit 102 whichinterconnects the valve 100 to the aforedescribed conduit 91, therebeing interposed in the latter conduit a pressure-controlled poppetvalve 103 which is under the influence of the pilot valve 98, being alsoconnected for its control to the conduit 99, as shown in Fig. 1. Thusthe conduit 102 is also divided into two portions, namely, a portion102a which is interposed between the valve 100 and the poppet 103, andthe portion 102b which interconnects the poppet valve 103 with theconduit 91.

The in-pressure regulating valve 100 is provided with a suitablemanually adjustable knob 100a by which the inpressure or back pressurecan be controlled which acts against the fluid under pressure coming viathe cam controlled valve 59.

Although one of the principal objects of the present invention is toprovide novel means for maintaining a minimum uniform contact pressure(rewind roll vs. contact drum pressure) during the build-up of therewind roll, such pressure sometimes being referred to as kiss pressure,such uniform minimum pressure is normally applicable for the rewindingof relatively light, thin and stretchy web material. In the case ofslitting and rewinding of substantially heavier and stiffer webmaterial, it may be desirable, in lieu of the minimum uniform pressure,to substitute a relatively heavier pressure which should be, however,maintained at a uniform value throughout the build-up of the rewindrolls. This can be achieved by the adjustment-of the in-pressure valves100 and 10Gb (Fig. 1').

The poppet valve 103 is analogous in operation to the poppet valve 97and blocks off or isolates the in-pressure regulating valve 1% wheneverthe handle 82 is' moved away from its central or run position.

The extent of the aforementioned in-pressure controlled by theregulating valve 100 can be determined by observing a gauge 104 which isin communication with the conduit 91. 1

Wealso have found it desirable to'ap ply a pressure axially of therewind shafts 21' and 22 against the cores upon which the rewind rollsare wound and such pressure may be applied by suitable fluid pressuremeans as shown in the lower portion of Fig. 1 wherein it will beobserved, for example, in connection with therewind shaft 21 that apressure sleeve 105 is employed which is urged to the left by means of apiston rod 166 which is under the influence of air pressure within acylinder 107 in a Well known way. Such pressure is conducted to thesleeve 105 by means of a crank 108 which presses against a rod 109 andthence upon an intervening plate 110. Air under pressure is conducted tothe cylinder 107 by means of a conduit 111 which is in communicationwith the main fluid supply cylinder 80. There is a hand-controlledpressure adjusting valve 112 interposed in the conduit 111, the pressurebeing adjustable by observing a gauge 113.

System for balancing web pull torque (brought about by center rewindtorque) against belt pull torque (brought about by the drive belt forefiecting center rewind torque), both torques acting about the supportarm pivot axis Referring now to Figs. 1, l and 11, there will bedescribed a system for balancing:

(a) the torque which is exerted upon the rewind'shaft support arms(acting about the pivot axis thereof) which is attributable to the pullof the web as it is wound upon the rewind shaft under the influence ofthe torque applied directly to the rewind shaft (center rewind torque);and

(b) the torque acting upon such support arms also about the pivot shaftaxis thereof, which torque is attributable to the belt driving means forthe rewind shaft.

A general analysis of the objectives of the system for balancing webpull torque and center rewind torque against one another requires theconsideration of the following facts:

The contact drum is driven, in the embodiment shown, at a constant speedand each rewind shaft is driven at a gradually diminishing speed, suchspeed control being accomplished by means shown in the aforementionedpatent to T. N. Carter No. 2,650,039. The invention, however, is notnecessarily l'imitedto this particular type of speed control but we havefound it to be advantageously adapted to this invention. Furthermore,the invention is not limited to the driving of the contact drum at aconstant speed with the rewind shaft being driven at a graduallydiminishing speed. For example, it would be possible to drive thecontact drum at a changing speed but with the rewind shaft being drivenat a speed differential (compared to the contact drum) which isanalogousto that occurring when the contact drum is driven at such a constantspeed or angular velocity.

Thus the present apparatus employs what is known in the art as centerrewind and contact rewind, that is the rewind torques are respectivelyattributable to: a driving torque exerted on the rewind shaft per se,and a torque occurring because of the peripheral contact between therewind roll and the driven contact drum. In view of the fact that centerrewind is employed (that is, a direct driving of the rewind shaft), theweb inescapably is placed under a tension because of the torque actingupon the rewind shaft. Such tension produces; a reaction. which (in thecase of the front shaft shown) forms a moment known as a web tensionmoment and which tends to urge the rewind shaft support arms 23, 24toward the contact drum thereby to alter the contact pressure, that is,to alter the pressure between the periphery of the rewind roll and thecontact drum. It. is such alteration of contact pressure which thisbalance system seeks to avoid. The webtension moment, of course, mayurge the support arms in the opposite directions, as in the case oftherear rewind arms. However, in this particular, example regarding suchfront support arms 23-, 24, the webtension moment tends to increase andthus to increase the contact pressure as rewind diameter (R) increases.However, the invention is not limited to such an increasing web tensionmoment. Thus, it is a further object of this balance system to minimizethe effect. of such, web tension moment, whatever its direction ormanner of changing, or to reduce its effect to negligible proportions bybringing intoplay a countertorque, attributable to the endless band orbelt means which drives the rewind shaft.

In: those cases where no center rewind torque is exerted on therewindshaft, there is no need for counterbalancingsuchweb.tension momentattributable thereto because the latter will. not arise. Thus, such acenter rewind. torque must. exist in, order for this particular balancesystem to be brought into play. However, such a center rewind torqueisnot necessary for the operation of the two static weightcounterbalancing systems herebefore described, I

In general, we have found that anadvantageous way tocouriter'balancesuch web pull is to drive the respective rewind shaftsby belt means wherein an endless belt or bandpasses over a rewind shaftpulley, preferably coaxial with and keyed to the rewind shaft, and alsopasses over a drive pulley which is located near the respective pivot oraxis of the support arms. By offsetting in a special way the axis of thedrive pulley, with respect to the. axis of thepivot shaft, we have foundthat an adequate compensation for the aforementioned web pull can beattained, suchrcompensation or counterbalancing being effected-by acounterbalancing moment which in turn acts against the moment which isattributable to web pull. That is, a counterbalancing torque isautomatically exerted upon the supportv arms about the axis of theirpivot shaft,,whichcounterbalancing torque differs onlyto a negligibledegreeor not a t-all with the torque acting uponsaid arms attributableto the web pull.

An analysis of the procedure. whereby the direction and-the extentofoffset of the aforementioned axis of the drive pulley with respect tothe axis of the pivot shaft, will now be set forth.

Referring now to Figs. 1,10, 11 and 11a, the, rewind shaft 21 ispreferably driven by means of endless band means, such as. anendlessbelt ll lwhich respectively passes over: a rewind shaft pulley115 secured to and coaxial with the rewind shaft21, and'o'ver a drivepulley 116. The direction and extent of offset of the axis or pivot ofthe latter pulley results in the counterbalancing ofweb pull as hereinset forth; We'have found it advantageous, but not mandatory, for thebelt 114 to be of flexibiematerial, for example, oftough steel wirebonded together'with or impregnated by a rubber-like material,

the belt having formed on the inner surfaces thereof a plurality ofparallel transversely extending ridges 114a (Fig. 10) which areuniformly spaced and designed for meshing with complementary ridges orteeth upon the peripheries of. the pulleys 115 and 116. A positive drivethereby isattained.

The pivotaxis (or primary axis) of the front supporting,arrns 23, 24 isindicated'by 117, whereas the pivot axis of the drive pulley 116isindicated at118 and is offset therefrom in a direction and by. anamount' as hereinafter set forth.

In view of the extent and direction of offset of the axis 118 withrespect to axis 117, it will be seen that suitable slack take-up meansmust be employed for the belt 114. Such means comprise a slack take-uproll 119 (Fig. mounted upon a lever arm 120 which is mounted for pivotalmovement upon a pivot shaft 121 and which lever arm is resiliently urgedagainst the inner run of the belt 114 by suitable means, such as apneumatic power cylinder 120a. Such slack take-up means preferablyshould engage the belt on the run thereof which is opposite to the runwhich effects the belt tension reaction for balancing the web pull.

As is well shown in Fig. 10, the web of material to be slit and rewoundis first unwound from a parent roll 122, such web being designated 123,and passes over the several rolls as shown through a tension controldevice 124 and thence via a roll 125 onto the contact drum 29 againstwhich the slitting is effected by means of a plurality of slitterwheels, one of which is shown at 126.

Each of such wheels is mounted upon suitable supporting arms, one end ofwhich is angularly shiftable about a fixed pivot and the other end ofwhich is urged toward the contact drum by means of a pneumatic powercylinder 127 which receives air under pressure via a conduit 128.

The rear rewind shaft 22 is driven in a manner analogous to the frontshaft 21, by means of an endless belt 129 of similar construction and inwhich the slack is taken up by a slack take-up device 130 which is urgedagainst the outer run of the belt by means of a pneumatic cylinder powerdevice 131.

The terms and abbreviations herein employed refer, for illustrationonly, to the front shaft system and are as follows:

B=Belt moment arm about the arm pivot, i. e., the perpendicular distancefrom the arm pivot axis 117 to a line tangent both to drive pulley 116and rewind shaft pulley 115 (such tangent following along one run of thebelt). I

W=Web tangent moment arm acting about the arm pivot 117, i. e., theperpendicular distance from the arm pivot axis 117 to a line tangent tothe rewind roll (contact drum) at the point of contact between such rolland drum. Such tangents are shown at 117a and 117b (for minimum andmaximum values of rewind roll diameter).

T=Belt tension (pull on drive belt), acts in a given direction about thearm pivot, i. e., acts in the direction of the tangent described inconnection with B.

P=Web tension reaction (must produce a moment opposed to that of T),acts in the direction of the tangent described in connection with W.

D=Diameter of contact drum 29.

d'=Diameter of drive pulley 116.

d=Diameter of rewind shaft pulley (e. g. 4.186") (Note:d and d are equal.in the form shown but can be unequal.)

R=Rewind roll diameter. 7

X =Distance between arm pivot 117 (primary axis about which rewind shaftsupport armspivot) and drive pulley axis 118.

=Angle, as measured clockwise about the arm pivot axis 117 (Fig. 11between: (a) The center line 23:: between the arm pivot axis 117 and therewind shaft axis 21 at some selected rewind roll diameter, e. g., 3/2"; and (b) The line from the arm pivot axis 117 to the drive pulleyaxis 118. v

A=Angle between points 1' and 1' as measured from the center oftheconstant drum, that is, the angle between the two points of tang' encybetween the rewind roll and contact drum with R-at its minimum andmaximum values respectively. 2

M=The radius of the supporting arm for the rewind shaft.

Now referring to Fig. 11a, the following general calculations andequations should be considered:

1) Belt tension moment or torque on arm (about arm pivot or primaryaxis) due to belt pull=T(B).

(2) Web tension moment or torque on arm (about primary axis) due to webreaction:P(W).

(3) Desired relation of such torques is as R builds up.

(4) For convenience, the term P(W) (web tension moment) should beobtained in terms of belt tension T, whereby an easy comparison of thetwo opposing moments can be made in view of the fact that belt tensionmoment is also in terms of T.

Therefore, consider an equation of the torques or moments about the axisof rewind shaft 21 (Fig. 11a):

to counterbalance belt tension moment TB as closely as possible duringrewind roll build-up, i. e., during increase in R, that is, whereby:

TB R

(or substantially so) the direction of offset (45) and extent of offset(X) of the axis of the drive pulley is selected to bring about the aboveequation as closely as possible as R builds up.

That is, when:

TB is substantially balanced by dTW B is so balanced by (as R variesbetween its limits, e. g. 3 /2 to 20"), then X and are determined. ThusX and g5 are selected to bring about the aforementioned balance orsubstantial balance as R varies.

Bearing in mind the two basic formulae to calculate the pertinentmoments due to web tension and belt tension (in terms of belt tensionT), namely, web tension moment:

W 4.l8 6 X I: Rewind diameter and belt tension .moment BxT, thefollowing table of moments is arrived at,.assuming that the rewindpulley diameter is, for example, 4.186" and that the FRONT ARM WEBlVIQMIlNT-TORQUE IVIOMEN'I and the drive pulley ANALYSIS Towards ContactDrum Away from Contact Drum (W) Web Tension Belt Rewind Web TangentMoment in Moment Belt Ten. Dia., Mom. Arm Terms of Belt Arm (B), Mom.inches A bout Arm Tension T inches Pivot, inches 3% 1.08 1. 3T 1. 05 1.05T 5 1. 3 1.09T 1.0 1. OT 7 1. 48 885'! 95 95'1 9 1. 82 848T 90 90'1 122. 39 835T 84 8 4T 15 2. 97 4-. 8ST 79 791 20 4. 08 856T 75 751 From thetable of moment arms and moments above set forth, and with particularreference to Fig. 11, it will be seen that the belt moment arm B variesbetween the respectivemaximum and minimum values B and B namely, from105" down to .75" and also that the web tangent moment arm W variesbetween the values W (minimum) to W (maximum) and that these valuesrespectively are 1.08 inches and 4.08 inches. Thus the belt moment armdiminishes by approximately 25% whereas the web tangent momentarmincreases in the neighborhood of 400%.

We have found that there is an adequatecounterbalancing of the webtension moment by the belt tension moment, as shown in Fig. 12, when thevalues of B and W vary, as shown in the table above set forth.

We have found it desirable to select the diameter D of the contact drumand the location of the arm pivot in such a way that as the rewind rolldiameter R increases, the angle A'isrelatively small, say, of the orderof l5 whereby the web moment arm W will vary, for example, from aboutl-to 4, as shown in Fig. '11. Thereafter, the drive pulley pivot ispositioned to produce a diminishing value of B as R increases, that is,the rewind roll diameter increases. Preferably, the length of arm M(Fig. 11) is about equal to the distance between axis 117 and the axisof drum 29.

It would be desirable to locate the arm pivot for the front arm-(Fig.11') in such a way-that the value of W varies between limits that aresubstantiallythe same as those ofthe rewind roll diameter. -Fr:example,in the present example, the rewind roll diameter varies between 3 /2"and 20", which by ratio is from '1 to approximately. Practical designconsiderations which limit the size of the apparatus, however, indicatesome difficulty to cause Wto vary-between 1 and 5%, as aforementioned,andin fact in the form shown we have'found that'such variationadvantageously "is "between '1 and about 4. Consequently to compensatefor the inability of the value W to increase by the desired'ratio(comparable to that of the rewind roll), the location of drive pulleypivot axis'is selectedin such awaythat the value of B diminishes, forexample, by approximately 25% with respect to thefront arm system; Withrespect to the rear arm, the decrease is, in that example, somewhatgreater,'the conditions, however, being somewhat different withrespectthereto.

Referring now to the rear arm of Fig. 11, it will be seen that thedirection' of the web moments (e. g. 119 for 22:20") acting upon therewind shaft supporting arm act 'in a counterclockwise direction due tothe attitude of the rewind roll with respect to the contact drum andalso due to the angle at which the web moves off of the contact drum andonto the rewind roll. In view of this, the belt tension reactions (e. g.120 for R 20) must be in an opposite direction and clockwise, the webreactions beingco-unterclockwise. That is, since the web reactions withrespect to the rear arm tend to move the arm away from the contact drum,the belt reactions must tend to move it toward the contact drum.

With respect to the front arm, the web reactions obviously urge the armtowards the contact drum and consequently the belt reactions must urgesuch arm away fromthe drum in order to counterbalance same.

In the determination of X and without making an exhaustive mathematicalstudy of the determinants therefor, it will be seen that the principalmission is to select X and in such a way that (as R varies from itsminimum to its maximum value) B should equal as closely as possible Astudy of this equation indicates that one of the initial determinants isthe quotient are in this special instance (where d=4.l86") 1.095 and.2095. Thus the quotient i is a diminishing function, diminishing in theratio roughly from 5 down to 1. It is found, in this particular case,that d B -W if B varies between 1.08 and .75 as shown in the tableabove.

Referring to the front arm of Fig. 11, one example of the values of X,4) and M are: 1.36; 313; 30';-and 14" respectively.

There is thus provided a novel slitting and rewinding apparatus whichachieves superior results in the control of roll density, internaltension and quality of roll edge and which meets'the most exactingquality control demands at heretofore unattained production rates, the

apparatus being capable of reaching speeds up to 2,000 7 ft. per minutedepending upon the widthof the web and its character. The novelapparatus provides in a single machine heretofore unattained versatility'in that itsis capable of slitting and :rewinding the following" typesof web material: light, heavy, stretchy, rigid, laminates, waxed andcoated papers, kraft, foil, impregnated fabrics., Rewind rolls produced.on this apparatus provide the precise degree of softness or hardnesswhich may be required for'shipping, storage and subsequent end use. Theautomatic rewind density control herein described is adjustablewhile-running, for example, by adjustment of the in-pressure controlvalve and/or'lfiilb, and

alsoby the adjustment of the indicators 66 and/or 66a (Fig. 1).

Furthermore, suitable means are employed for posi tively isolating therewind tension, that is, the tension of the web as it leaves the contactdrum, and the so called unwind tension, namely, the tension of the webas it is unwound'from the-parent roll.

The slitting of the web can be accomplished by any one of theseveral'well known means, one of which'is shown in the aforementionedpatent to" N. Carter The consistently accurate means for controlling theaforementioned rewind roll vs. the contact drum pressure substantiallyeliminates operator guesswork during the operation of the apparatus.Also rewind rolls of unvarying quality are assured. Once a satisfactoryrun for any type of material has been achieved, the setting oradjustments of the apparatus permit perfect reproduction of suchsatisfactory run and the pressure, sensitivity and wide range of controlmeans provides optimum running conditions for a heretofore unattainedvariety of materials. By eliminating the aforementioned guessworkheretofore incidental to hand set adjustments in prior art apparatus infavor of highly sensitive control means, such as the pneumatic system ofFig. 1, the novel apparatus insures constant dependability on longrewind runs.

The present invention employs a combination surface and center rewindprinciple, that is, the rewinding of the rewind rolls is effected bydriving the rewind shaft (center rewind) and also by driving the contactdrum, the latter being rotated at a constant angular velocity (surfacerewind). The rewind rolls are rewound in twoseparate groups, as is wellknown in the art, one group being on the front rewind shaft and theother group on the rear rewind shaft, the individual rewind rolls beingstaggered on the separate shafts and well separated, thus effecting apositive roll separation.

By virtue of the neutralization of the torques, heretofore occurring inprior art apparatus, namely: (a) those exerted upon the support arms ofa given rewind shaft, attributable to the static weight of the rollmaterial as it builds up; (b) also those attributable to the staticweight of such arms and shaft; and (c) the torques incidental to webpull and "center rewind, a precisely controllable contact pressure(rewind vs. contact drum pressure) is attained by the differentialbetween the pressures on opposite sides of the pneumatic powercylinders, e. g. 53 and 54. By the use of such pressure differential,heretofore unattained accuracy of quality control is attained,particularly with respect to roll density.

Although only a single embodiment of the present invention has beenillustrated and described in detail, it is to be expressly understoodthat the invention is not limited thereto. For example, regarding themeans for counterbalancing the static weight of the support arms andrewind shaft, instead of the counterbalancing springs, such as 30, 31 or42, 43, other suitable means can be employed in other forms of theinvention, such as a counterweight system adjusted to counterbalance theaforementioned static weight as the support arms shift angularly. Alsoregarding the system for counterbalancing the static weight of therewind rolls as they build up, in lieu of the particular pneumaticcounterbalancing system as shown in Fig. 1 employing the pneumaticcylinders (for example, 53, 54 acting on the rear support arms), it ispossible in other forms of the invention to employ other force exertingdevices which .can create a torque or moment acting upon the supportarms which is counter to the moment due to the action of gravity uponsuch rolls as their diameter increases. For example, a mechanicalcounterbalancing of this type may be employed, including acounterweight, which may be shiftable along a scale beam by, forexample, electrical means in response to the angular movement of a givenpair of support arms or to the extent of movement of the axis of therewind (or roll) shaft from a norm position as in the embodiment ofFig. 1. That is, the countermoment for counterbalancing the staticweight of the rolls can be efiected in other embodi ments by means whichcan be actuated in response to movement of the axis of the rewind shaftfrom some norm and employing, of course, the density of the material asone of the governing factors. In connection with the counterbalancing oftorque upon the support arms attributable to web pull (brought about bycenter rewind torque) in substitution for the endless belt with thedrive pulley axis offset from the support arm pivot axis herein 16 shownand described, there may be employed a gear train linkage from asuitable power source, such as a motor, operatively connected to therewind shaft. In Fig. 11b, an example of such a linkage is showndesignated by the numeral 132. Only one of such linkages will bedescribed for one of such support arms, it being understood that asimilar gear train may be employed for the other support arm of a givenpair. A support arm 133 rotatably supports a rewind shaft 134 at itsupper extremity and is pivotally mounted at its lower extremity 135. Therewind shaft has secured thereto a gear 136 which is operativelyconnected to a motor 137 through the intermediary of the gear trainshown which comprises six toothed consecutively meshing gears 138-143,inclusive, the pivot shafts of which are'mounted upon the support arm133. The feature of the modification of Fig. 11b, which is analogous tothe offset pivot feature of Fig. 11, comprises a driving gear 144(analogous to drive pulley 116), the axis 145 of which is offset fromthe pivot arm axis in a manner analogous to the offsetting of the axisof the drive pulley pivot, as shown in Fig. 11. The driving gear 144 isdrivably connected to the gear train 138143 through the intermediary ofgears 146 and 147 which are mounted upon a lever arm 148. One extremityof the lever arm 148 is pivotally secured to the arm 133 at 143a leverarm 148 is pivotally secured to the arm 133 at 143a, comprising the axisof the gear 143, and at the opposite extremity of the arm 148 the gear147 is rotatably mounted about an axis 147:: comprising the pivot axisof the gear 147. A supplementary arm 149 is pivotally mounted at oneextremity at 147a and at the opposite extremity at the pivot and is ableangularly to shift about the latter pivot which is fixed. The pivot 135also is fixed. As torque is applied to the drive gear 144, it will exerta torque upon the support arms 133 via the arm 148 which is analogous tothe torque exerted upon the support arm, for example 24 (Fig. 1), by thebelt 114.

In a separate and non-equivalent embodiment of the invention, in lieu ofmounting the rewind shaft upon support arms, such as 23, 24, such armsmay be dispensed with and the opposite extremities of the rewind shaft,e. g. 21, can be supported in suitable tracks formed, for example, ineither straight or curved parallel slotted or grooved members, suitablemeans being provided, of course, to prevent the rewind shaft frombecoming askew or canted with respect to such slotted members. Suchmembers are provided with said tracks for receiving the oppositeextremities of such a rewind shaft and for guiding same, for example, insubstantially the same curved path as shown in Fig. 11 although suchcurved path may be straight.

What is claimed is:

1. In a winding machine, the combination of: a pair of rewind arms, arewind shaft, means for pivotally supporting said arms at their innerends for angular movement about a primary axis, said arms being adaptedto support said rewind shaft at their outer ends on which shaft a webofsheet material is to be rewound into a rewind roll,- a driven contactdrum with which such roll is in engagement during the rewinding thereof,a driven -pulley mounted for rotation near the outer end of one of saidarms and drivablyconnected to said rewind shaft, a drive pulley mountednear the opposite extremity of said arm for rotation about a secondaryaxis, and an endless belt interconnecting said pulleys for communicatingtorque to said rewind shaft to wind such web thereon,'means for mountingsaid drive pulley with its axis of rotation comprising such secondaryaxis spaced from said primary axis by a selected distance in a selecteddirection for achieving a balance between the moments acting upon sucharms attributable to the tension of such belt and the moments actingupon said arms attributable to the reaction of such web as it is woundupon such shaft while the diameter ofsuch re- .wind roll. ingreases.

never-as 2. In a winding machine, the combination of: rewind arm means,a rewind shaft, means for pivotally supporting said arms at one endthereof for angular movement about a primary axis, said arms beingadapted to support said rewind shaft at the other end thereof forangular movement therewith about such axis, and on which shaft webmaterial is to be wound into one or more rewind rolls, a contact drummounted for rotation in the path of such angular movement of such rewindshaft,

pulleys, such web being fed to said rewind shaft for being woundthereupon, and passing partly around said drum thereby to create webtension moments acting on said arm means in one direction about saidprimary axis in response to driving such rewind shaft, said endless beltmeans creating belt tension moments acting on said arm means about suchaxis in response to driving said drive pulley, means for mounting saiddrive pulley with the axis of rotation thereof comprising ,saidsecondary axis parallel to but spaced from said primary axis by aselected distance and in a selected direction for creating such webtension moments in an opposite direction about said primary axissubstantially to balance said belt tension moments while said rewind.roll increases in diameter.

3. Apparatus in accordance with claim .2 wherein said belt tensionmoment=BT andsaid web tension .moment WdT R and further where WdTsubstantially, where: B is the perpendicular distance from the arm pivotto a line tangent both to the drive pulley and to the rewind shaftpulley as the rewind roll builds up; W is the perpendicular distancefrom such arm pivot to a line tangent to the rewind roll at the point ofcontact between the latter and the contact drum; and T is the belttension or the tension on the drive belt; d is the diameter of the drivepulley; and R is rewind diameter.

4. In a winding machine, rewind arm means 'pivotally supported at oneend thereof for angular movement about a primary axis, and adapted tosupport a rewind shaft at the other end thereof, on which shaft webmaterial is to be wound into one or more rewind rolls, a contact drummounted for rotation about a stationary axis and positioned in the pathof movement of the axis of rotation of said first-mentioned shaft, suchangular movement occurring about the aforementioned primary axis,whereby web material passing at least partly around said contact drum iswound upon such rewind shaft, power means operatively connected to suchrewind shaft for winding such web of sheet material thereupon, thereby,to create the aforementioned rewind rolls, the winding of such rollsupon such rewind shaft creating web tension moments about theaforementioned primary axis, means for operatively interconnecting saidrewind shaft with a power source for driving same, means for mountingsuch operative interconnection with respect to the aforementionedprimary axis for creating a substantially equal and opposite momentabout the primary axis .substantially balancing the web tension momentas the rewind roll increases in diameter.

5. In a winding machine, rewind arm means pivotally supported at one endthereof for angular movement about a primary axis, and adapted tosupport ,a rewind .shaft at the other end-thereof, which shaft is.adapted in turn for the winding thereupon of web material in Qneior morerewind rolls; a contact drum mounted for rotation about a stationaryaxis parallel to the aforementioned primary axis and to the axis ofrotation of said rewind shaft; spring means operatively connected withsaid arm means for counterbalancing the static weight of said arm meansincluding that of said rewind shaft; means responsive to angularmovement of said arm means from a' norm position for exerting a torqueon said arm means as a function of such angular movement thereby tocounterbalance the static weight of the web material wound upon saidrewind shaft, said arm means angularly moving in response to the build.up of web material upon said rewind shaft; driving means for saidrewind shaft comprising an endless band passing over a rewind shaftpulley connected to said rewind shaft and positioned near the outer endof said arm means, said band also passing over adrive pulley, the axisof rotation of the latter pulley being positioned near to but offsetfrom said primary axis by a selected distance in a selected directiontherefrom responsive to the variation of B as compared to the variationof where: B is the belt moment arm about the aforementioned primaryaxis, that is, the perpendicular distance from such axis to a linetangent both to the drive pulley and the rewind shaft pulley; d is thediameter of the rewind shaft pulley; W 'is the web tangent moment armabout such primary axis, that is, the perpendicular distance from theprimary axis to a line tangent to the rewind roll and contact drum atthe point of contact between such roll and drum; and R is the rewindroll diameter; and such distance and direction being selected wherebythe differences between B and as R is increased, are of negligibleamount.

6. In a winding machine, rewind arm means pivotally supported at one endthereof for angular movement about a primary axis, and adapted tosupport a rewind shaft at the other end thereof, which shaft is adaptedin turn for the winding thereupon of web material in one or more rewindrolls; a contact drum mounted for rotation about an axis parallel to theaforementioned primary axis and to the axis of rotation of said rewindshaft; driving means for said rewind shaft comprising an endless bandpassing over a rewind shaft pulley connected to said rewind shaft andpositioned near the outer end of said arm means, said band also passingover a drive pulley, the axis of rotation of the latter pulley beingpositioned near to but offset from said primary axis by a selecteddistance in a selected direction therefrom responsive to the variationof B as compared to the variation of where: B is the belt moment armabout the aforementioned primary axis, that is, the perpendiculardistance from such axis to a line tangent both to the drive pulley andthe rewind shaft pulley; d is the diameter of the rewind shaft pulley; Wis the web tangent moment arm about such primary axis, that is, theperpendicular distance from the primary axisv to a line tangent to therewind roll and contact drum at the point of contact between such rolland drum; andR is the rewind roll diameter; and such distance anddirection being selected whereby the differences between B and 385R isincreased, are of negligible amount.

19 7. In a winding machine, rewind arm means pivotally supported at oneend thereof for angular movement about 'a primary axis; a rewind shaftsupported at the other end of such arm means for rotation about an axiswhich is parallel to said primary axis, said rewind shaft being adaptedfor the winding of web material 'therearound in one or more rewindrolls; a contact drum mounted for rotation about an axis parallel to theaforementioned primary axis and to the axis of rotation of said rewindshaft, said rewind rolls and drum being in peripheral contact when themachine is in operation; and means for selectively controlling thepressure of such contact independent of the static weight of such armmeans, shaft, rolls, and of a web reaction torque set forth below, suchmeans including: means operatively connected with said arm means forcounterbalancing the static Weight thereof including the static weightof said rewind shaft, means responsive to the extent of angular movementof said arm means about said primary axis for exerting a torque uponsaid arm means acting about said primary axis, such torque being afunction'of the extent of such angular movement thereby tocounterbalance the static weight'of such web material wound upon saidrewind shaft as such weight increases, means for driving said rewindshaft thereby to rewind said web material thereon, the driving of saidshaft producing a web reaction torque acting on said arm means, meansfor mounting said driving means for producing a torque whichsubstantially counterbalances said web reaction torque, and adjustablemeans for exerting force for urging relative movement of said drum andshaft.

8. In a winding machine, arm means pivotally supported at one endthereof for angular movement about a primary axis, a driven shaftsupported at the other end of such arm means for rotation about an axiswhich is parallel to said primary axis, said shaft being adapted for thewinding of web material therearound in one or more rolls; the driving ofsaid shaft producing a web reaction torque acting on said arm means, andmeans for balancing said web reaction torque.

9. In a winding machine, a rewind arm device pivotally supported at oneend thereof for angular movement about a primary axis; a rewind shaftmounted for rotation at the other end of such rewind arm device, suchrewind shaft being driven and being positioned for rotation about anaxis parallel to such primary axis and being adapted for the winding ofweb material thereon in one or more rewind rolls; a contact drum mountedfor rotation about an axis parallel to the aforementioned axes, saidrewind rolls and drum being in peripheral contact when the'machine is inoperation; and means for making the pressure of such contact independentof the static weight of such rewind arm device, rewind shaft, rewindrolls and of a web reaction torque set forth below, such meansincluding: means operatively connected with said arm device forcounterbalancing the static weight thereof including the static weightof the rewind shaft mounted thereupon, power means for exerting torqueupon said arm device, and means for controlling said power means inresponse to the angular displacement of said arm device from a selectednorm position,

such angular displacement being in turn responsive to change in diameterof such rolls whereby the static Weight of web material wound upon saidrewind shaft is counterbalanced, the aforementioned web material passingat least partially around said contact drum and thence being Wound uponsaid rewind shaft and exerting a torque upon said arm device about saidprimary axis attributable to web tension reaction resulting from suchshaft being driven as aforesaid; driving means for driving same asaforementioned and this for said rewind shaft for applying a drivingtorque thereto, and means for mounting said driving means for producinga torque for substantiaily counterbalancing said web reaction torque.

10. In a winding machine, a rewind arm devicei pivot- "20 ally supportedat one end thereof for angular movement about a primary axis, a rewindshaft mounted for rotation in'the other end of said rewind arm deviceabout an axis which is parallel to said primary axis, said rewind shafthaving a torque directly applied thereto for the winding of web materialthereupon in one or more rewind rolls out from a parent roll; a contactdrum mounted for rotation about an axis parallel to the aforementionedaxes, said rewind rolls and drum being in peripheral contact when themachine is in operation; primary counterbalancing means operativelyconnected with said arm device for counterbalancing the static weightthereof including the weight of the rewind shaft mounted thereupon; saidprimary counterbalancing means comprising spring means operativelyconnected with said arm device for deformation in response to angularmovement of said. arm device from a selected norm position whereby theaforementioned counterbalancing of such static weight is effected;secondary counterbalancing means for counterbalancing the static weightof the web material as it is wound up upon said rewind shaft andcomprising means for exerting a torque upon said arm device in responseto the angular movement of said arm device from a selected norm positionas the diameter of the rewind roll thereupon builds up; said webmaterial being wound upon said primary shaft creating a web tensionmoment about the aforementioned primary axis responsive to the drivingof said rewind shaft which moment varies as such rewind roll diameterbuilds up; and tertiary counterbalancing means for substantially fullycounterbalancing the aforementioned web tension moment as the lattervaries in response to the build-up of rewind roll diameter.

11. In a winding machine, the combination including: a pair of rewindarms pivotally supported at one end thereof for angular movement about aprimary axis, a rewind shaft mounted upon the other ends of said rewindarms and positioned there for rotation about an axis which is parallelto said primary axis, said rewind shaft being adapted for the windingthereupon of web material in one or more rewind rolls; a contact drummounted for rotation about an axis parallel to the aforementioned axes,said web material passing at least partially around said contact drumand onto said rewind rolls upon said rewind shaft, said rewind rolls anddrum being in peripheral contact; the static weight of said rewind shaftand rewind arms exerting a moment about the aforementioned primary axis,primary counterbalancing means for exerting a primary torque upon saidrewind arms thereby to counterbalance the aforementioned static weight,such primary torque being a function of the extent of angular movementof said rewind arms from a selected primary norm position; a furthertorque being exerted upon said rewind arms about the aforementionedprimary axis as a result of the static Weight of the web material woundthereupon in said rewind roll or rolls, said torque varying in responseto the build up of the diameter of said roll, secondary counterbalancingmeans for exerting a secondary counterbalancing torque upon said rewindarms for counterbalancing the aforementioned further torque due torewind roll static weight, said secondary torque exerting means beingresponsive to the angular movement of said rewind arms from a secondarynorm position as rewind roll diameter increases; the aforementioned webmaterial passing at least partially about said contact drum exerting aweb tension moment upon said rewind arms responsive to the driving ofsuch rewind shaft, such moment acting about the aforementioned primaryaxis, and tertiary counterbalancing means for exerting a tertiarycounterbalancing torque upon said rewind arms thereby to counterbalancethe aforementioned web tension moment as the latter varies in responseto the building up of rewind roll diameter.

'12. In a winding machine, the combination of: a contact drum, a rollshaft on which sheet material is to be wound in one or more rolls, drivemeans connected to said roll shaft for rotating same thereby to windsuch sheet material thereupon, the axes of said roll shaft and contactdrum being so disposed with the Web of sheet material being Wound uponthe roll shaft under tension and exerting a force upon such roll shafttending to cause relative movement of the axis of such shaft withrespect to that of the contact drum, and means for counterbalancing suchforce.

13. In a winding machine, a driven roll shaft adapted for the windingthereon of web material in the form of a roll, a contact drum, the forceof gravity acting upon said roll shaft due to the mass thereof, suchforce of gravity also acting upon the sheet material Wound thereupon inthe form of such roll, a further force acting upon said rewind shaftattributable to the tension of the sheet material as it is wound uponthe roll shaft by virtue of the fact that such shaft is driven asaforementioned, such forces tending to cause relative movement of theaxis of such roll shaft and the axis of such contact drum, such contactdrum and material rolled upon the roll shaft being peripherally inengagement during the winding of the web material thereon, and means forrespectively neutralizing such forces during the driving of such rollshaft and thus as the distance changes between the axis of said contactdrum and the axis of said roll shaft.

14. In a winding machine, a roll shaft adapted for the winding thereonof web material in the form of .a roll, a contact drum, power meansconnected to said shaft for exerting a driving torque thereon fordriving same and thereby winding such material thereon, the force ofgravity acting upon said roll shaft due to the mass thereof, such forceof gravity also acting upon the sheet material Wound thereupon in theform of such roll, a further force acting upon said rewind shaftattributable to the tension of the sheet material as it is Wound uponsuch roll shaft by virtue of the fact that such shaft is driven asaforementioned, such forces tending to move the axis of such roll shaftwith respect to the axis of such contact drum, means for respectivelyneutralizing such forces during the driving of such roll shaft and thusas the distance changes between the axis of said contact drum and theaxis of said roll shaft, such contact drum and material rolled upon theroll shaft being peripherally in engagement, and means for exerting acontrolledlforce for urging said axes toward one another.

References Cited in the file of this patent UNITED STATES PATENTS1,267,080 Judelshon May 21, 1918 1,964,076 Petersen et a1. June 26, 19342,190,106 Peterson Feb. 13, 1940 2,196,000 Richardson Apr. 12, 19402,609,157 Asmussen et a1. Sept. 2, 1952 2,650,039 Carter Aug. 25, 1953FOREIGN PATENTS 13,782 Great Britain of 1908 UNITED STATES PATENT OFFICECERTIFICATE OF CORRECTION I Patent'No. 2,872,126 February 3, 1959'Leonard Rookstrom et .al

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction and that the saidLetters Patent should read as corrected below,

Column '7, line 68, for 'cusioning" read h cushioning column 8, line 14,for "plating" read placing column ll, line '70, for "constant" readcontact column 19, line '70-, claim 9,. beginning With "driving means"strike out all to and including "torque thereto", in line '72,. same 7column, and insert instead driving means for vsaid rewind shaft fordriving same as aforementioned and thus for applying a driving torquethereto I Signed and sealedthis 8th day of September 1959.

Attest:

ROBERT C. WATSON Commissioner of Patents Attesting Officer

